Periodontal Health Literacy and Chitosan Mouthwash Self-Care as Determinants of Oral Health Knowledge and Gingival Index Improvement

Background: Periodontal diseases remain a public health concern among school-aged children in Indonesia. In Semarang City, Central Java, signs of gingival inflammation persist despite school-based oral health programs. Although health literacy interventions are widely implemented, their clinical impact remains inconsistent. Objective: This study evaluated the effects of an integrated intervention combining periodontal health literacy education with adjunctive chitosan mouthwash on oral health knowledge and gingival status. Methods: A quasi-experimental study with repeated measures was conducted from January to June 2025 among 118 Grade V students from public elementary schools in Semarang City, Indonesia. Participants were assigned to four groups: combined intervention, mouthwash only, health literacy only, and control. Oral health knowledge was assessed using a validated 20-item questionnaire, and gingival status was measured using the Gingival Index at baseline and follow-up (days 3, 5, 7, and 12). Data were analyzed using a generalized linear model with repeated measures. Results: Significant improvements in gingival index were observed across intervention groups, with differential effects over time (p < 0.05). Knowledge improvement was significant only in the combined intervention group and did not differ significantly between groups. Clinical improvements were more consistent than knowledge gains. Conclusion: The integration of periodontal health literacy education with practical self-care strategies, including chitosan mouthwash, demonstrated short-term effectiveness in improving gingival health among school children.